The National Geographic Society/Waitt Grants Program’s Brennan Phillips and his expedition team captured film from inside Kavachi. According to National Geographic, Phillips and Co. felt safe exploring the depths of the ocean because they couldn’t hear it rumbling. Really:

“But one of the ways you can tell that Kavachi is erupting is that you can actually hear it—both on the surface and underwater. Anywhere within 10 miles even, you can hear it rumbling in your ears and in your body.” No one heard rumbling, so they prepared to go right to the rim of the crater.

“These large animals are living in what you have to assume is much hotter and much more acidic water, and they’re just hanging out,” Phillips says. “It makes you question what type of extreme environment these animals are adapted to. What sort of changes have they undergone? Are there only certain animals that can withstand it? It is so black and white when you see a human being not able to get anywhere near where these sharks are able to go.”

Great. Super sharks in an underwater volcano lair. That’s cool. Everything’s fine. Totally going to be able to sleep tonight.